Commit 40ac7ab2 authored by Miklos Szeredi's avatar Miklos Szeredi
Browse files

fuse: simplify 'nofail' request 



Instead of complex games with a reserved request, just use __GFP_NOFAIL.

Both calers (flush, readdir) guarantee that connection was already
initialized, so no need to wait for fc->initialized.

Also remove unneeded clearing of FR_BACKGROUND flag.

Signed-off-by: default avatarMiklos Szeredi <mszeredi@redhat.com>
parent 1f4e9d03

fs/fuse/dev.c

+4 −60
Original line number Diff line number Diff line
@@ -242,52 +242,6 @@ struct fuse_req *fuse_get_req_for_background(struct fuse_conn *fc, 
}

EXPORT_SYMBOL_GPL(fuse_get_req_for_background);



/*

 * Return request in fuse_file->reserved_req.  However that may

 * currently be in use.  If that is the case, wait for it to become

 * available.

 */

static struct fuse_req *get_reserved_req(struct fuse_conn *fc,

					 struct file *file)

{

	struct fuse_req *req = NULL;

	struct fuse_inode *fi = get_fuse_inode(file_inode(file));

	struct fuse_file *ff = file->private_data;



	do {

		wait_event(fc->reserved_req_waitq, ff->reserved_req);

		spin_lock(&fi->lock);

		if (ff->reserved_req) {

			req = ff->reserved_req;

			ff->reserved_req = NULL;

			req->stolen_file = get_file(file);

		}

		spin_unlock(&fi->lock);

	} while (!req);



	return req;

}



/*

 * Put stolen request back into fuse_file->reserved_req

 */

static void put_reserved_req(struct fuse_conn *fc, struct fuse_req *req)

{

	struct file *file = req->stolen_file;

	struct fuse_inode *fi = get_fuse_inode(file_inode(file));

	struct fuse_file *ff = file->private_data;



	WARN_ON(req->max_pages);

	spin_lock(&fi->lock);

	memset(req, 0, sizeof(*req));

	fuse_request_init(req, NULL, NULL, 0);

	BUG_ON(ff->reserved_req);

	ff->reserved_req = req;

	wake_up_all(&fc->reserved_req_waitq);

	spin_unlock(&fi->lock);

	fput(file);

}



/*

 * Gets a requests for a file operation, always succeeds

 *
@@ -301,25 +255,18 @@ static void put_reserved_req(struct fuse_conn *fc, struct fuse_req *req) 
 * filesystem should not have it's own file open.  If deadlock is

 * intentional, it can still be broken by "aborting" the filesystem.

 */

struct fuse_req *fuse_get_req_nofail_nopages(struct fuse_conn *fc,

					     struct file *file)

struct fuse_req *fuse_get_req_nofail_nopages(struct fuse_conn *fc)

{

	struct fuse_req *req;



	atomic_inc(&fc->num_waiting);

	wait_event(fc->blocked_waitq, fc->initialized);

	/* Matches smp_wmb() in fuse_set_initialized() */

	smp_rmb();

	req = fuse_request_alloc(0);

	if (!req)

		req = get_reserved_req(fc, file);

	req = __fuse_request_alloc(0, GFP_KERNEL | __GFP_NOFAIL);



	req->in.h.uid = from_kuid_munged(fc->user_ns, current_fsuid());

	req->in.h.gid = from_kgid_munged(fc->user_ns, current_fsgid());

	req->in.h.pid = pid_nr_ns(task_pid(current), fc->pid_ns);



	__set_bit(FR_WAITING, &req->flags);

	__clear_bit(FR_BACKGROUND, &req->flags);

	return req;

}
@@ -342,9 +289,6 @@ void fuse_put_request(struct fuse_conn *fc, struct fuse_req *req) 
			fuse_drop_waiting(fc);

		}



		if (req->stolen_file)

			put_reserved_req(fc, req);

		else

		fuse_request_free(req);

	}

}
@@ -719,7 +663,7 @@ void fuse_force_forget(struct file *file, u64 nodeid) 


	memset(&inarg, 0, sizeof(inarg));

	inarg.nlookup = 1;

	req = fuse_get_req_nofail_nopages(fc, file);

	req = fuse_get_req_nofail_nopages(fc);

	req->in.h.opcode = FUSE_FORGET;

	req->in.h.nodeid = nodeid;

	req->in.numargs = 1;

fs/fuse/file.c

+1 −1
Original line number Diff line number Diff line
@@ -432,7 +432,7 @@ static int fuse_flush(struct file *file, fl_owner_t id) 
	if (err)

		return err;



	req = fuse_get_req_nofail_nopages(fc, file);

	req = fuse_get_req_nofail_nopages(fc);

	memset(&inarg, 0, sizeof(inarg));

	inarg.fh = ff->fh;

	inarg.lock_owner = fuse_lock_owner_id(fc, id);

fs/fuse/fuse_i.h

+1 −7
Original line number Diff line number Diff line
@@ -435,8 +435,6 @@ struct fuse_req { 
	/** Request completion callback */

	void (*end)(struct fuse_conn *, struct fuse_req *);



	/** Request is stolen from fuse_file->reserved_req */

	struct file *stolen_file;

};



struct fuse_iqueue {
@@ -580,9 +578,6 @@ struct fuse_conn { 
	/** waitq for blocked connection */

	wait_queue_head_t blocked_waitq;



	/** waitq for reserved requests */

	wait_queue_head_t reserved_req_waitq;



	/** Connection established, cleared on umount, connection

	    abort and device release */

	unsigned connected;
@@ -927,8 +922,7 @@ void __fuse_get_request(struct fuse_req *req); 
/**

 * Gets a requests for a file operation, always succeeds

 */

struct fuse_req *fuse_get_req_nofail_nopages(struct fuse_conn *fc,

					     struct file *file);

struct fuse_req *fuse_get_req_nofail_nopages(struct fuse_conn *fc);



/**

 * Decrement reference count of a request.  If count goes to zero free

fs/fuse/inode.c

+0 −1
Original line number Diff line number Diff line
@@ -617,7 +617,6 @@ void fuse_conn_init(struct fuse_conn *fc, struct user_namespace *user_ns) 
	refcount_set(&fc->count, 1);

	atomic_set(&fc->dev_count, 1);

	init_waitqueue_head(&fc->blocked_waitq);

	init_waitqueue_head(&fc->reserved_req_waitq);

	fuse_iqueue_init(&fc->iq);

	INIT_LIST_HEAD(&fc->bg_queue);

	INIT_LIST_HEAD(&fc->entry);

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